China targets five U.S. subsidiaries of South Korean company Hanwha Ocean, sending its shares down 8%

China added five U.S. subsidiaries of South Korean shipbuilder Hanwha Ocean to its sanctions list on Tuesday over their alleged involvement in Washington’s investigation into China’s maritime industry, escalating tensions between Beijing and Washington.

The sanctioned subsidiaries include Hanwha Shipping LLC, Hanwha Philly Shipyard Inc., Hanwha Ocean USA International LLC, Hanwha Shipping Holdings LLC and HS USA Holdings Corp, according to a statement from China’s Ministry of Commerce.

The order, which took effect immediately, will prohibit Chinese organizations and individuals from doing business with the sanctioned companies, the statement said.

The move follows the U.S. decision to impose high fees on Chinese ships docking at U.S. ports starting Tuesday at 12:01 a.m. EDT.

China retaliated by imposing a similar tax of 400 yuan ($56) on American ships, starting the same day.

Beijing also unveiled a new framework to restrict exports of rare earths and expanded its blacklist of U.S. companies.

In response, US President Donald Trump threatened to impose 100% additional tariffs on Chinese imports, prompting Beijing to view its restrictions on rare earths as a “legitimate” measure.

Shares of Hanwha Ocean in Seoul plunged more than 8% after the announcement.

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